Effect of housing and husbandry practices on adrenocortical activity in captive Canada lynx (Lynx canadensis)

Abstract

In recent years, there has been an increasing focus on the study and assessment of animal welfare in captive settings, such as zoological gardens and aquaria. Canada lynx (Lynx canadensis) are a relatively common species in zoos, yet are known to exhibit frequent reproductive problems in captive environments. We provide an exploratory analysis of housing and husbandry factors that are associated with patterns of adrenocortical activity in lynx. Adrenocortical activity was assessed using the non-invasive technique of monitoring faecal glucocorticoid metabolites (FGM). First, we calculated baseline FGM values for each individual and controlled for sex, age class, and reproductive status. The residual values were used to determine how levels of adrenocortical activity correlated with institutional husbandry practices. Second, we compared the occurrence of FGM peaks to events and disturbances recorded by keepers. Our results highlighted that adrenocortical activity is strongly correlated with: (i) the size of the enclosure; (ii) the number of hiding locations available; and (iii) the social environment. Based on our findings, we recommend that lynx should generally be housed alone (unless with dependant offspring or temporarily paired up for mating purposes), in larger enclosures and with the provision of several species-appropriate hiding locations.

Validation of an enzyme immunoassay for the measurement of faecal glucocorticoid metabolites in Eurasian (Lynx lynx) and Iberian lynx (Lynx pardinus)

“…Besides husbandry conditions, veterinary procedures are also correlated with high fGM levels in different carnivore species (Malmkvist and Hansen, 2001;Rothschild et al, 2008;Young et al, 2004), but wherein especially the chemical immobilization represents a potential stressor for captive animals (Teixeira et al, 2007). In contrast to other studies demonstrating that translocations and acclimatisation to new enclosures caused strong stress responses in felid species (Carlstead et al, 1993a;Fanson and Wielebnowski, 2013;Wells et al, 2004), in our study distinct elevated fGM concentrations following translocation were only measurably in a single male (Fig. 6).…”

“…This could be due on the fact that some of the stress events were not recognised by the keepers, potentially depending on the keepers' anthropocentric perception of the environment (Fanson and Wielebnowski, 2013). In addition the samples were not collected on a regular basis.…”

Monitoring the behavioral and adrenal activity of giraffe (Giraffa camelopardalis) to assess welfare during seasonal housing changes.

“…GC are one of the major components of the stress response (Sapolsky, 1992) and GC monitoring has been documented in previous research as a useful tool for managing animals in professional care. Fanson and Wielebnowski (2013) found that size of the enclosure was one of the main factors that correlated with GC secretion in Canadian lynx. In this study, one individual had lower GC concentrations when moved from a small enclosure to a significantly larger one.…”

“…Effects of season on GC concentrations has been observed in zoo giant pandas, in which an individual in one study had higher GC concentrations in the winter and spring than in the summer season (Owen, Czekala, Swaisgood, Steinman, & Lindburg, 2005). Both studies used GC collection techniques that were non-invasive, one through fecals (Fanson & Wielebnowski, 2013) and the other through urine (Owen et al, 2005). These methods are valuable techniques and potentially more accurate by not having increased GC secretion caused by captureinduced stress (Millspaugh & Washburn, 2004;Millspaugh et al, 2001).…”

Lynx canadensis (Carnivora: Felidae)

“…Recommended minimum enclosure size per Lynx canadensis is 4 by 2 by 2.5 m (l by w by h) and floor area should be increased by 50% for each additional cat (Mellen 1997). Individuals should have access to at least 75% of the vertical space (Mellen 1997) along with several hiding locations (Fanson and Wielebnowski 2013). Clawing activity should be stimulated by providing rotting logs in the enclosure (Mellen 1997).…”